Sidecar Technical Hints and subframe mounts

Sidecar Technical including mechanicals, photos, licensing, alignment, etc.
© Copyright, 2011, R. Fleischer
sidecartech.htm
sidecar section item 2

NEED FAST INFORMATION???:
For instant advice on the Web, try the Yahoo sidecar LIST, see information in the sidecarbasics.htm article on this website, and in the url.htm article.

There are other manuals, etc., available from various sources, such as the USCA...one is called Driving a Sidecar Outfit...often called the Yellow Manual. There is also one that was a translation from German that has a lot more technical information, called "Riding with a Sidecar". This was translated and is available in America.....THAT...and some other quite valuable additional materials is available from Hal Kendall....who has a LOT of information (4 manuals) available on ONE CD he produced...which UPDATES that manual....or, better said, is the updated manual. This CD is entitled: Sidecar Manual, Sidecar Operator Manual, Sidecar Catalog, Riding with a Sidecar.
You do not have to get the CD....as...the same information is available free, all 4 of the books, at http://www.sidecar.com/links3.asp

However, you CAN, if you want, get Hal's stuff on CD-ROM, for only $10.00; contact him directly at
hal-kendall@worldnet.att.net or hkendall1@houston.rr.com

The information is also available for free at: http://autos.groups.yahoo.com/group/SCT/files/SC%20Driving/

NOTE: I have some disagreements with a few places in some books about driving a sidecar outfit; and, with the organization, Evergreen, and its policies and methods and what I feel are some errors in content. MY MAJOR disagreement (all my other's are nitpicky) is with the description of counter-steering and steering reversion, which I feel is WRONG!

The serious sidecarist REALLY SHOULD own at LEAST Hal's CD, or print out the information from the above website.

Here is a link to that Evergreen sidecar training organization:
http://www.esc.org/

LICENSING and OPERATION:
The licensing requirements for operating a sidecar outfit vary from State to State. Besides the licensing requirements, the way Authorities treat sidecar operators in MANY ways, is very different. Here are a few things of possible interest:

Authorities of various sorts are INconsistent in fee structures for sidecar outfits for such as toll use of bridges and the like. Some Authorities, or their automatic in-pavement sensors, are very confused by sidecars having three axles. Many sidecars have the sidecar wheel ahead of the rear tire of the tug....called the LEAD amount. That makes them THREE axle. Harley's and some others may have their sidecars with the axles in line with the tug. Tolls are often based on the number of axles. Some sidecarists have had this clarified with their States, some with the various Authorities, many have not. Hal Kendall has taken it upon himself to be very vigorous with the various Authorities on this situation, so if you have problems with toll-takers, PLEASE get a receipt, and contact Hal, his e-mail address is above!!!

Requirements for helmet use is a bit muddled. In California, before roughly 1981, this was complicated due to the number of axles...due to a definition of the old Class 3 license being necessary for 3-axle vehicles grossing less than 6000 pounds. I won't get into this deeply here, as it is no longer the situation...suffice to say the following....In California, which is the State I am most familiar with, LICENSING of the drivers is not now at all complicated, as the requirements were finally, after requests from such as Doug Bingham (and his taking a DMV-appointed Raymond Soon for some hack rides...Mr. Soon was appointed to investigate the problems), back around 1981, were finally straightened out and spelled out in law and interpretation of law. Before this, the DMV and CHP had not agreed on things between themselves, let along others. So, back then, after they agreed, a rig could be driven with a Class 3 license....which INcluded a Class 1. Confused? These classes were all changed, so, enough on those. Suffice it to say that a CAR license is adequate.

Today....... California has two types of motorcycle driver's licensing's...two CLASSES as they call them. TWO-wheeled motorcycles require either a Class M1 or M2 driver's license.

Class M1: can operate ANY two-wheel motorcycle rated at 150 CC or more...and may operate all vehicles listed under M2.

Class M2: can operate ANY two-wheel motorcycle rated at 149 CC OR LESS, or a vehicle called a 'motor-driven cycle', or one called a 'motorized bicycle'. These two types are spelled out as to meaning in the codes. NOTE!... People driving in California often see, on freeways, a sign prohibiting Motor-Driven Cycles. Basically it means if you have 15 or more horsepower, you are OK on that road, and if less than 15 horsepower, you are a forbidden Motor-Driven Cycle.

Here's where it gets to be fun!.....

The Class-C car driving license....the one most everyone has.......has specifics about axles, trucks, gross weights, and so on....but....regarding sidecar rigs...it specifically states that this license Class-C is OK for operating a motorcycle with a sidecar attached....'OR a three-wheeled motorcycle'. They define these terms too, elsewhere's. Thus, trike's are covered, as are sidecar rigs. RESTATING...a motorcycle with a sidecar attached requires only a regular Class C driver license....the same license needed to drive a car in California. I have both a C and an M1 license. I can drive a motorcycle, a sidecar, a trike, and some trucks...besides cars. In California, there is no provision in the law to require a motorcycle license in order to drive a sidecar rig. HOWEVER, they DEFINE a motorcycle to INCLUDE a sidecar rig. That definition is over-ridden by the LICENSING requirement for DRIVING a rig. The reason this seeming-at-first-glance to be conflicting, but is not, is for the various other provisions in the Vehicle Code. One can refer to the Code, sections 400 and 27803. If you have been following all this, you might ask if someone who has NO car license, but only a M1, can drive a sidecar rig. Welcome to gray areas!

In California, all motorcycle riders and passengers are required by law to wear a legally approved helmet. There is NO provision in the law to EXclude sidecar passengers....note, again, that the definition of a motorcycle includes sidecars, but LICENSING of operation spells things out as above.

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General notes and hints, will be expanded on over the years:

Rims:
Do NOT try to install a 15 inch car tire onto a 15 inch motorcycle rim, unless you are absolutely sure you know what you are doing. A 15 inch car tire is designed for a 14.968" rim; a 15" motorcycle tire is designed for a 15.080" rim. Does not sound like much, but may be enough difference for a serious explosion. If the rim is fat enough/thick enough, it may be possible to turn it on a lathe. Maybe. Maybe not. BEWARE!

The above caution, AFAIK, does not apply to 16 inch and 17 inch wheels and tires.

Sidecar folks sometimes use rear tires on the front of the tug, with the directional arrow, if present, reversed. This is acceptable practice, even admittedly so by such as Metzeler.
It is possible to seal a tube stem via rubber washers and exterior nut to the rim to hold air better, if the tire/tube is punctured. But, that must be offset with the knowledge that if the tire rotates any on the rim, it could rip the stem out of the tube. Thus, one should understand that, in truth, for stock bikes, the tube nut is for help in installing the tube, then to be NOT used....or to be up against the valve CAP, NOT the rim.

BMW makes a special all-metal valve stem that fits in original valve stem holes, but is for tubeless tire use....and it comes with the core, metal cap, nut....and rubber O-ring. part 36-32-1-452-748 a NICE part! This type of part is available at 1/3 the price, elsewhere's. Some rims are not flat on the inside, and will require spot-facing for this item.

Sidecar folks sometimes do all sorts of things that are not necessarily consider OK on a solo two-wheel motorcycle.

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Photos of my BMW-Ural rig.

This is a 1983 BMW R100RT and a Ural hack; other views are in photogallery.htm on this site.

The tug has a dual-plugged engine with raised compression ratio, the front forks are UNIT, with stock dual Brembo brakes. The rear drive is 3.36:1. The rear brake is the stock single Brembo disc brake. Front wheel size is 19 inch, rear wheel size is 18 inch. Rims are stock. I have two rear wheels, one has road rubber, the other has an Enduro tire. The sidecar tire and rim are stock Russian Ural items, 3.50 x 18. The left side of the tug has a Luftmeister 1 gallon auxiliary fuel tank. A very long list of other modifications have been made. The fairing is stock BMW "RT" type, and the lowers are still in place, although the right side one is modified for the upper strut of the sidecar attaching. The attachment to the tug is via a subframe of the Lowell Neff style, somewhat modified from his design. Even though of steel, the joints and fitments were HELIARC'd. There are two upper struts and two lower ball mounts. The subframe, photos later herein, picks up numerous points on the tug frame. There are some frame beefups on the tug, nothing major, but what WAS done was deemed important. There have been ZERO problems since this rig was put together in 2001.

The photo below is of me, at one of the Griffith Park Sidecar Rallies.

Below photo was taken January 12th, 2005, a bit over two months before a much nicer spare tire carrier was installed

BELOW is a view of the added hack brake pedal, made from a salvage yard aluminum BMW pedal. I cut off the L section from the left side of the pedal, and welded it onto the right side of the added pedal. A long piece of steel round rod was added to the sidecar brake rod angularly under the sidecar for additional strength;... the angle was to help to avoid any bending, then that rod was welded to a somewhat shortened Ural slotted lever, and then bent downwards and then extended to the left, towards the bottom in this photo. The rod then had an additional round rod welded to it, for the BMW stock brake pedal to push against. Note how the modified pedal presses only on the Ural's brake rod, but the tug's brake pedal presses on that AND its own, stock, hydraulic cylinder.

Thus the two brake pedals are independent. Normal stopping is done with the tug's stock pedal, which applies a light braking to the sidecar wheel at the same time. If the other pedal is used, the sidecar braking can be done separately, and as much braking as desired, independent of the tug brake. This can be very useful for tight right turns.

The mounting for the added pedal is a special shoulder bolt, to maintain a tight assembly without noticeable play. A small spring keeps the pedal from vibrating, at its tip, onto the brake rod. An adjustable stop, hard to see at the top here, sets the amount of distance the pedal is off the brake rod.

Another view of the dual pedals, and also showing the upper rear strut. The pedal on the left is the stock BMW pedal for the rear brake. Notice that actuating the BMW rear brake applies pressure onto the sidecar brake, but the sidecar brake pedal activates only the sidecar brake. The hack pedal came from a BMW junkyard, and its toeplate is a bit different, it is centered, not offset....but any version would do. Not shown is the underside of the right pedal, which I slightly modified with a common file, so that the sidecar brake will have limits. Due to the normal, stock, limited travel of the BMW pedal on the left, and careful adjustment of the Ural brake adjustment nut (on the Ural wheel brake rod), it is not possible to lock, or overly brake, the sidecar wheel, from the BMW stock pedal on the left. This worked out PERFECTLY! Thus, this setup is 100% mechanical without ANY tug rear disc brake hydraulic changes, and very reliable, for braking of the sidecar wheel. This SAME sort of thing would be easy to do on a BMW tug with drum rear brake.

This is the subframe that is on the right side of the R100RT. The upper portion at the top of this photo fits the ADDED cross piece above the stock area battery. The lower part, horizontal, attaches to the rear frame, the rear footpeg, other places, and to both engine bolts. This is a Lowell Neff design. It is exceedingly sturdy.

((NOT pictured: the upper front mount, which mounts at the BMW frame cross piece, just under the steering head)). There are TWO ways of doing that part, one is welding, one is a special sturdy clamp. I dislike welding on the BMW frame, and used a clamp....in fact I purchased mine directly from Lowell Neff. It places front strut forces directly into the existing, stock, BMW frame AND BMW STOCK CROSSPIECE.

Below are some views of the struts; steering damper setup (with several hole adjustments), front and rear lower mounts, and a rear view. The clamp and plate assembly for the steering damper was made with several holes, so it could be made adjustable for stroke and other effects. The damper is a VW type, and there is only ONE Heim joint, and the sidecar upper strut end of the damper has the stock damper's rubber mount in the 'eye'. Originally two Heim joints had been used, but I found this to have, due to the complex angles of use, too much effective movement before damping began, and thus a lot of time was spent getting just the right angles and clamping, so I could eliminate one Heim joint. There is ZERO instability, no wobbles, etc. The stock BMW hydraulic steering damper still exists, but is not powerful enough, hence the VW damper. It would be possible to set the added damper mounting plate holes further inward, for LESS stroke, and less steering effort, if the BMW damper was turned on to position 1 or 2. Dampers, whether hydraulic or friction, are always a compromise, too much damping makes for heavy handling, too little can allow the front end to oscillate badly. Each rig is different.

NOTE!....The VW Beetle damping unit is used by a LOT of sidecarists. It is important that it be used correctly, or poor return of the steering to straight ahead, will be seen, and stiff steering (higher forces). For some folks, use of the Beetle, NOT Super-Beetle, damper, may be better....for some, the Super is better. The VW standard Beetle damper can be attached to some tugs by replacing an upper shock mounting bolt...with a Heim attachment. Try to avoid using two Heims in your installation, it often gives rise to excessive movement before dampening. The end of the standard Beetle damper is 10 mm, and if one can not get a 10 mm threaded Heim...sometimes hard to find....then one could consider using a 3/8" Heim, and run a 3/8-24 tap over the 10 mm end. The other end of the dampener attaches to the front strut...you can weld on a tab, or use a clamp, or whatever is really needed.

In MY installation, I use the standard dampener end of 90 degrees as shown, and bolted a Heim to it, and the strut end is a bolt-on clamp (after all, the strut needs adjustability). I kept the rubber bushing in the eye of the dampener, it was needed. Originally, I'd tried two Heim's, one at each end, but this allowed excessive movement before dampening began...and, tiny as that was, it made me have to use a attachment hole on the fork clamp...see photo.....that was too far away from the fork, and whilst that gave enough dampening stroke action, it also increased the EFFORT for steering. By carefully aligning the design, I eliminated the eye end Heim, moved the attachment at the fork closer to the downtube, and that reduced stroke amount per steering amount...a NICE effect. For those that can eliminate the rubber bushing, you will be even better off.

These are special Hagon shock units, the preload is adjustable by the upper shiny collar. I found the lowest setting just fine. At the upper center area is shown some of the stock BMW oil cooler. The shocks and spiral wrapped SS brake lines all came from Heddingham (UNIT FORKS) of England. Spring and dampening of this sort of design should be such that under VIGOROUS braking, the suspension NEVER extends to rock-solid limits. If that happens, braking will be 'skipping'. NOTE!...UNIT has changed hands. It is now owned and run by: Broomhill Composites Ltd. Sales@unitsidecars.co.uk

Note the damper mounting clamp-plate assembly, and the damper Heim is in the third hole from the end, that is, it is in a very close-to-fork tube position. It gave enough dampening, without making the steering too stiff. Use of a square front tire, the Avon Triple Duty Sidecar tire, installed AFTER this photo was taken, allowed me to move the pivot one hole inwards, for less dampening, and even easier steering effort. The clamp(s) at the top of the Hagon units are adjustable up and down on the UNIT front ends. This changes the TRAIL!

All that speckling is sand and gravel pitting, primarily from 7 trips to Alaska!

This shows the front Ural mount, notice the additional bolt on it! Installation was done in such a way as to INcrease the track width by about 3 inches; for easier access to valve adjustments;....see following photos about the rear mount. The rear mount is similarly beefed with an additional bolt. NOTE that the stock Ural front mount is NOT adjustable. I cut that one off, and obtained another rear type (there are at least two versions, they all can work OK here at the front), and notice the beefed up angular plate. There is a VERTICAL beef-up plate that is hardly visible just barely to the left, underside, of the two clamp bolts. This may be way overkill, but makes me comfortable!

The next two photos are of the right side of the tug, showing what I crudely did to the right side lower fairing piece. The first photo shows that I cut this piece vertically, so there is a REAR half and a front half. For the purposes of this photo, I put something (hidden) inside to move the rearmost part outward slightly, to better show the cut, in white here. By unfastening at the bottom fasteners that go to the stock metal bracket (not shown), and at the top (see second photo, inside area, where I made a simple beef-up plate), the parts are removable without having to remove the strut, bottom mount, etc.

Below is of the inside area...crudely done, but effective

This view shows the extension piece that was made up, that allowed the wheel lead to be reduced to 6 inches, a rather low amount, but one that is very easy on tires and has quick handling. The drawback is that one must be more cautious about overly-vigorous turns away from the sidecar, lest the sidecar nose go over and dig in, a very BAD thing to have happen! I do NOT recommend that most folks use 6 inches of lead on this type of rig. 9" or 10" would likely be safer for them. The photo might lead you to believe that the extension is not parallel to the hack and bike frames, but that is not so. NOTE the additional bolt on the Ural sliding mount. Note that this modification was done (and the front mount too!) such that the TRACK WIDTH of the bike-to-sidecar, was INcreased, by roughly 3 inches. That allowed for the proper access for servicing, and also I felt would make for somewhat more stable driving on common road track widths. The former more important than the latter.

This is the initial setup, with the Ural fender rack and the Ural rear rack, I am carrying a spare front tire here in this photo.

Below is a photo of the final modification of the above mount, rack, etc., completed 03/19/2005, that enabled me to carry a spare BMW snowflake rear disc wheel/tire. I can put another tire on top of the rack, or lots of luggage. In order to do this, and preserve the use of the neat looking Russian cap, the Russian welding at the bottom of the mount was ground away, and a 6 inch long metric 8.8 grade bolt, with the same end threads as the Russian cap (12 x 1.75 mm), was welded from the bottom upwards. The stock large thick Russian washer under the mount was first drilled with a large drill that was just a bit larger than the diameter of the bolt's head, this allowed the bolt head to be recessed nearly 3/4 of its head thickness. That eliminated any chance the bolt would contact the trunk lid, and added a bit of length to the bolt, which I found was needed. I then welded the bolt head to the Russian washer. A spacer was made for the wheel bearing axle opening in the wheel, so that the wheel would not move about on the long bolt, as the wheel bearing inside diameter was considerably larger than the 12 mm bolt. That spacer was made from an old piece of chrome luggage rack round tubing. A thick flat spacer, counterbored to fit the BMW internal axle spacer, which sticks up slightly from the bore, was used between the wheel's disc hub, and the underside of the Ural rack. This made for a VERY neat installation. On the Ural chrome rack on the fender of the sidecar is a 2-1/2 gallon plastic fuel container I sometimes travel with. It's weight is just where sidecar weight should be...over the wheel! I can put a much larger Jerry can there, if I wanted to. A 5 gallon Jerry can and fuel would likely weigh about 40 pounds, and be the equivalent of considerably more sidecar passenger weight, and the rig could be expected to NOT lift its wheel in right turns very easily at all. The Ural chair is a heavy one anyway. The ride, for a passenger, is very comfortable, indeed, with the stock Ural suspension system.

More photos below: The top two photos show the round solid steel spacer that transmits hack upper rear strut forces to the right side of the tug frame, and then via that added spacer, to the left side of the tug frame. This spacer is located over the battery area, using EXISTING and UNused BMW frame holes.

This is the 'crudely' modified battery tray. I'm not proud of this workmanship! Surrounding that jagged hole and not easily identified is an aluminum sheet metal piece that is inside the tool tray, it is riveted and then sealed to the inside base.

Notes on Setup and Alignment

1. One of the very first things to decide upon when first building a rig, is the amount of wheel lead, if any. Wheel lead is the amount the sidecar wheel axle is forward, if any, of the tug's rear wheel axle. Early rigid frame tugs, such as the Harley Davidson, can use zero lead. A racing outfit might use as much as 15 inches. GENERALLY, modern bikes with modern suspensions will use 6 to 12 inches.    With zero lead, there is little scrubbing on the tires on turns, but weight distribution is poor, and any tendency to nose over (rear wheel lifting on turns away from the sidecar) is worse (the rigid frame tugs are much better at avoiding this). Added weight to the front wheel is poorer for handling. If the tug weight is massive, the tendency to nose over is lessened. As the sidecar wheel lead is increased, the sidecar wheel takes more load, the weight on the front wheel is reduced.   As the sidecar wheel is moved more and more forward, the more tire scrubbing will be had on turns. In fact, the sidecar wheel can REVERSE during turns if too far forward.    As rear suspensions became less rigid, and the modern swinging arm was developed, sidecar lead needed to be increased. It is rather typical on a good handling and good compromise (tire scrubbing, ETC.) rig, for the sidecar axle to point to the front edge of the tug rear rim.      Further forward gives better weight distribution but more tire wear, further rear eases turning effort and less scrubbing. Ideally, the lead should be as small as possible.
2. The sidecar frame should be level, as measured on a level surface. That is, the sidecar wheel side of the sidecar frame....and the sidecar frame portion towards the tug, should be LEVEL.    Measure with normal weights in the sidecar and on the tug.
3. Toe-in: This needs to be checked with normal loading as with tug and sidecar, unless you find your rig will be stable with weight changes.   Toe-in is needed. It will help counteract the bias and drag of the sidecar due to the wind resistance and the wheel friction and drag.   Less drag means less toe-in can be used. Toe in is measured by many means, but is almost always measured off the rear wheel. Too much toe-in does NOTHING BUT INCREASE TIRE WEAR.    Zero toe-in is generally a bad idea.    While correct toe-in will correct for any tendency for the rig to pull towards the sidecar (not enough toe-in), that is very difficult for an amateur to figure out.     If you want to try, the correct toe-in is achieved when at about 30 mph on a DEAD FLAT ROAD, when there is no tendency to pull either left or right. The HUGE problem with this is that normally the tug is leaned OUTward, to compensate for road camber/tilt, and this greatly complicates things, as does finding a truly flat road. Best, for most, to take careful measurements, set the toe to some value, and work from there, slowly, ever so slowly, making small changes in toe and lean-out, ONE thing at a time.....until things are 'sweet'.   Toe-in amounts, in a big generality here, are generally about 1/4" to 1-1/2", with around 5/8" for more rigid tug rear suspensions and 1" for longer throw tug rear suspensions, as probably good values.

PAGES upon PAGES could be written about how to measure, repeatedly, toe-in, by inches, by degrees, etc. I won't get into it here. For toe-in, the measuring points are usually just ahead of the front tire, and just behind the rear tire.

NOTE! As lean out is increased, the sidecar wheel will tend to lift much more easily, NOT a good idea! There is controversy over lean-out. Some use Lean-In!...depends on the rig. As lean-out INcreases, it is easier for turns away from the sidecar, but the sidecar wheel can lift (fly) easier on turns towards the sidecar. Toe-in affects the amount of lean-out to be used. Too small of a toe-in will cause you to use more lean-out, with a very noticeable tendency for the sidecar wheel to come off the ground in turns towards the sidecar.

4.  Still finer-yet considerations:
a. To help compensate for road crown, and reduce the need for excessive leanout (sort-of), consider having the sidecar wheel side of its frame about 1/2" higher.
b. Consider having the front of the sidecar frame slightly higher than the rear
c. Consider having a minimum 44 inch track
d. Consider that toe-in changes towards LESS, as the speed increases, due to flex in all sorts of things.
e. If toe-in is too little, there may be a tendency to drift towards the gutter.
f.   If a rig is well set-up, it will move slightly towards the curve with acceleration, away with braking.
g. Some say that about 14% lead is best (of wheelbase).
h. Lean-out is supposed to be used strictly for compensating for road crown.    Be sure, if using a major multi-lane highway, to drive the rig in every lane, moving over slowly, to see the crown road effects.

Getting into this deeper...More notes on alignment, setting up of sidecars:

5. The main reason for adjusting the lean of the tug is so that you do not need constant left or right pressure on the handlebars, at the typical speed on the typical roads that you travel on (yes, a huge requirement and description). Constant pressure is VERY tiring, your shoulders will thank you for a properly set-up rig. If you travel on all sorts of different banked and crowned roads, you may want an electrically operated adjustable lean control (or, effectively the same thing by adjustment the sidecar suspension electrically). HOWEVER, a very properly set-up rig, built very stoutly, tends to not need them...but they can be NICE to have!

Adjustments to a sidecar rig tend...particularly on some rigs...to inter-react with each other. Many times it can take making small adjustments on ONE THING AT A TIME, to find the 'sweet spot'. There are some 'quickie' tests on your garage floor that can reveal
some things...such as placing a vertical stick on the floor, just barely in front of the center, horizontally, of the sidecar nose, have the nose of the sidecar an inch or so away from it. Place a bit of masking tape in the center of the nose of the sidecar. Have the steering straight ahead when you line the stick and masking tape. HOLD the REAR brake, and turn the bars full left, and then full right. What happens to the relationship between stick and masking tape, and, do you know WHY, and what it MEANS?

Every rig, properly designed and built, can have a SWEET SPOT...where handling, control, pressures, feel, all come together.....this place is often that of good tire mileage too!
Some very generally correct rules for alignment are:
Toe-in affects pulling right and left (if it pulls to the right, an increased toe-in will help compensate). The very bad part of this is that if the toe-in is excessive, you gain nothing but tire wear, and tire wear with a lot of toe-in can be HUGE.   For most common street-going rigs, toe-in over 1" is excessive, and I have found that most can do well with about 3/8". One issue NOT thought of by most, is that the condition of the sidecar wheel's suspension can have quite an effect on toe-in. Several ways. I will assume the bearing has no feelable play (if it does, fix it). I will assume the TUG suspension has no sideways movement either. Even things like weak spoke wheels can be affected during turns. Both tug and chair suspensions may be mounted in deteriorated rubber; or have loose fittings in some way.   Thus, toe-in can change while on the road.   One effect hardly ever thought of, I may have been the first to bring this up on the SCT list (??), is that the oncoming wind, and forces on the suspension(s) may well change the toe-in as speed increases. Even if it does not change the toe-in, there may be an EXCESSIVE effect by speed.   Think about it. Suppose you have a dead flat section of road near you, a nice place to do test drives. Let's say that you find that you have 'perfect' alignment on your bike, as far as handling goes. You can almost take your hands off the bars, and the rig will go straight down the road. BUT, as you increase speed, the oncoming wind has almost no TURNING effect on your TUG....but it DOES push on the nose and body of your SIDECAR. That causes the rig to try to turn towards the sidecar. You will compensate by turning the bars away from the sidecar. But, that is a constant pressure on the bars. It is possible to set up a rig such that this type of effect is minimal, but it can take time to fiddle to get the rig that way.   Everything dealing with sidecar rig
handling seems to take TIME!!!

I well remember being frustrated with my 1983 R100RT-Ural rig after doing a lot of alignment work. It just was way too speed sensitive. Why? Gads...why had I not thought about nose angle!...yep, some quite modest change in the nose angle cured that final handling problem. After that bit, the only thing left was to decrease steering effort specifically caused by the steering dampener. I made an adjustable plate to allow adjustment of the shock absorber's STROKE used for dampening. That fixed that problem. I now had a rig that I could put thousands of miles on in a tour, and be very happy. It took TIME to adjust things. ONE step at a time!

Please keep in mind that if the rig is not VERY stout, things may BEND, one way or the other, under pressure from cornering or even oncoming wind. Those things really put a fly in the ointment in trying to have a good handling rig.

Toe-in adjustments are, generally, a very bad way to try to cure pulling (left or right). Tire wear is the prime reason, but not the only reason. That is why lean-in and lean-out are the prime adjustments for pulling right or left. Toe-in also has an effect on how hard the rig is to turn left or right.   To most sidecarists (I think), they either don't know about this effect, OR, they can't feel it, or think they can not. If the toe-in is excessive, that makes the rig turn harder away from the sidecar (left for most in this country). Toe-in affects some other things. If your toe-in is too much, not only do you scrub away tire rubber on turns towards the chair, but the rig might tend to drift towards the middle of the road...and vice versa. Note also that if the toe-in is way too little, that you could find that you need way too much lean-out!....heck, even your front brake will act poorer!! Guess what happens with excessive lean-out!...yep, chair lifts easily....and...YOU guess!

Another thing that affects how hard it is to steer the rig, and even PULLING!... is the LEAD of the sidecar wheel. Here's another one of those things that few talk about. If the rig pulls to the RIGHT (towards the sidecar), the typical response is to change the LEAN of the TUG. However, DEcreasing the wheel lead will have a similar effect.

If the rig is hard to turn away from the chair; and hard to turn towards the chair, most think that they simply must have a leading link or Steerite, or, whatever. Maybe they do not know that DEcreasing the wheel lead will do SOMEwhat of the same easing of steering....and reduce pulling away from the chair at the same time. But, there is a limit to how far you can DEcrease the wheel lead, without leading to other niceties, such as the nose wanting to dig into the ground with overly-brisk left turns.   NOTE that, generally, if you use MORE wheel lead, then you can use LESS toe-in. If the wheel lead is excessive, the sidecar wheel can actually reverse during turns, and scrub its rubber off not-so-nicely. Generally, wheel lead is something you guess at, based on experience, and once set into the construction, it is very difficult to change, so most never try. Note that my discussion has not gotten into the straight-across NO wheel lead rigs, like some Harley's.....they are worthy of their own long discourse.   I make an educated guess on wheel lead AND toe-in, when first working on a new rig.

Lean:
NOTE that you can go too far with the lean adjustments.   As has been noted, if the sidecar lifts easily, you can DEcrease the leanout. But, you may not want to DEcrease leanout, maybe due to faster wheel lifting. What to do?   Here, again, is there is a NICE answer (the other nice one was that toe-in can be under 1" on most every rig). ADD WEIGHT to the sidecar itself. The farthest point on the sidecar away from the tug, is the best point. To the REAR of the sidecar is VASTLY better than the sidecar nose.   This is really something that is VERY nice about sidecars...weight is not much of an issue, if it is centralized or rearward on the chair.   Some have even put lead inside a right side frame. A nice thing is to have a car battery at the chair. It takes up room if put in the chair's trunk, so some clever
mounting might be needed. With today's no-maintenance batteries, putting one or two under the chair, toward the right side, is often very doable. You might even decide to eliminate the tug's battery. Reasons for and against, of course..    Some put extra fuel underneath the sidecar, centered or slightly toward the rear. Of course, as you use the fuel, that weight disappears.   I was going to build a custom tank for that on my Airhead-Ural rig, but sold it before I started construction. It was going to be 12 gallons. ...close to 100 pounds including the SS tank and mounts, down low, and well away from the tug. I would have been a real menace to Porsche's in the twisties!

Some rigs are just plain overly sensitive to alignment. By this I mean that adjusting one thing causes a quite noticeable effect on another adjustment. Most of the time this can be gotten rid of, with attention to details. It is amazing how many sidecarists are so LAZY that they will put up with an ill-handling rig, or with tire wear, or both; instead of taking the time, and it can be considerable, to get things really right.   Some have probably given up on sidecaring, due to poor handling rigs. In general (I use that word a lot), I try to align a rig based on my best guesstimates, and then...USUALLY...the lean-in or lean-out is the LAST adjustment I hopefully have to make. I also might put force on the sidecar suspension, after a long eye-ball look at it...to see if something is angularly moving, etc. A sidecar suspension that moves 1/8" is a VERY considerable amount, in effects.

Anyway, what all this chit-chat amounts to, is food for thought, and hopefully improved handling and tire wear.

Revisions:

05/24/2004: add link to driving manual and notes for others.
05/26/2004: Add numerous photos and explanations, re-arrange page
06/19/2004: Expand information on tires/tubes
09/04/2004: minor updates
10/26/2004: URL's
03/18/2005: update, rotate one photo, annotations improved, add notes on the rack modification for the snowflake wheel and make a place for a photo to be placed there in the future.
03/19/2005: modify notations on photos and add photo, enhance some photos for clarity.
05/25/2005: Add section on alignment
07/21-2005: slight corrections for clarity
07/24/2005: correct Hal Kendall's e-mail address
08/12/2005: lengthy note on the steering dampener Heims, etc.
03/16/2006: Final editing; add photos of right lower fairing area, update text; and full release
11/03/2006: Add URL for the free download of the Sidecar Manual
03/27/2007: Add hyperlink to Hal's manuals
07/22/2007: update hyperlinks and manuals information
01/09/2009: fix hyperlink
04/26/2010: remove bad Ural link
02/01/2011: add another link to Hal's books
05/09/2011: Add more notes on alignment

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